Improvement in machines for cutting sheet metal to an oval form



ittica affitti.

WILLIAM D. GRIMSHAW0F NEWARK, NEW JERSEY.-

Letters Patent. No. 110,354,- dated December 20, 1870.

IMPRQIIEMENT IN MACHINES FOR CUTTING SHEET METAL TO AN OVAL FORM.

The Schedule referred tg in these Letters Patent and making part of the same.

ATo all whom it may coi'zcern:

Be it known that I, WILLIAM D. GmMsnAw, of `Newark,in the county of Essex and State of New Jersey, have invented a new and useful Inl-- provement in Machines for Cutting Oval and other Curved Forms in lSheet Metal and other substances and I do hereby declare that the following is a full, clear, and exact description, reference being had .to the accompanying drawing forming part of this speci-l' ication, and in which- Figure l represents a sectional side elevation of a machine for cutting ovals and other-'curved forms, `ctmstructed in 4accordance with my invention Figure 2, a. plan of the same; and

Figure 3, an inverted plan of the revolving platecarrying block or table with its cross-slides.

Similar' letters of reference indicate corresponding parts.

My invention consists in a novel arrangement within or under the revolving plate-carrying block or table of the cross-slides in different planes, whereby said slides with their center-pins are made capable. of crossing each other and of working in closer relation as regards their center-pins, which enlarges the capacity of the machine and allows of ovals being cut, the major axes of which more closely approximate the minor axes thereof than is attainable by an arrangement of said slides in the same planeas heretofore adopted.

Theinvention also includesY an advantageous construction and arrangement of the clamp for holding. tle plate on the working-table and between it and a revolving disk attached to the clamp.

Likewise, a novel construction r 01' combination of parts fonsimultaneously releasing, when required, the shears from contact with each other, and the operating or driving-wheels of the shears from gear, the oneA with the other.

In the accompanying drawing- A represents thc bed of the machine, formed with a longitudinal slot, b, in V`it, for adjustment along it, relatively to each other and `to the headstock B that carries the shears of the bearings C C', in which the pins s s' of the cross-slides D `D' work, said slides being arranged within t-he plate-carrying block or table E, andserving, when the table is revolved, to secure, as in other machines, to the plate its necessary movements, which willlinsure a cut of oval orother curved shape being made in it by the action of the revolving shears F F', as said plate, in the turning of the vtable E, is passed between the shears.

But, instead of arranging these slides D D', as heretofore, in the same plane, so that the one cannot cross the other, I arrange them in different. planes, or the one above the other, whereby they may be crossed to opposite sides of each other, and

be made capable of working in closer relation to one another as regards their pivots or center pins s s', which enlargcs the capacity of the machine and -circles, as well as ovals or different irregular gures ,by the same machine; but it will suliice to restrict this description to the cutting of ovals.

The plate is held on the tabe E by a spring.

pressure clamp, composed of a disk, Gr, carried by a lifting-rod, H, which is free to'turn in a cranked brace or arm', I, secured at its lower end to the table E, and said rod H, having the spring J, which gives the necessary pressure to the clamp, wound around it.

This constitutes at once a simple and effective clamp, and allows of the introduction and adjustment of the plate on the table E, or between it and the holding-down and revolving disk G, without offering anyimpedimentl or hindrance, and allowing of the full sweep of the table to secure the cutting of the com plete iigure free from interference by the clamp with the headstock D.

rlhe revolving shears F F are driven by friction or other gears KK' arranged on the outer ends of their shafts L L', any suitable driving-power being applied to the one shaft L, which has a fixed bearing in the headstoclr B, while the other sha-ft L turns in a sleeve or bearing, M, of eccentric construction, made capable of adjustment within said headstock, and which may be turned as required by means of a handle, N. Y

By this construction of the parts not only may the one shear 1i" be stopped while the other shear is free to revolve by turning the eccentric so as to throw the.

gear K out of contact with the gear K, but, in so doing, `the two shears F and F are simultaneously thrown out of working contact with each other, which prevents wear and affords greater convenience in the handling and adjustment of the plate.

What is here claimed, and desired to be secured-by Letters Patent, is

1. The arrangement -of the pin-carrying slides D D' within the table E in different planes, whereby they are enabled tocross each other, substantially as specified.

2. The combination, with the table E, of the pressure-clamp, composed of the cranked brace or arm I, the lifting-rod H, and the disk G, the whole arranged to be capable of turning, essentially as herein described. f

3. The combination of the eccentric sleeve or bearing M, with the shears F F and friction-wheels KK', or other gears-,substantially as specified.-

WILLIAM D. GRIMSHAW.

hVit ne'sses:

FRED. HAYNES, R. E. RABEAU. 

